The invention relates to a method of cooling profiled rolling products hot rolled in rolling stands, especially rails on a cooling bed by natural convection or force air cooling. The invention is also directed to an apparatus for performing the above-mentioned method of cooling rails.
Rails are cooled on cooling beds down to a temperature below 80.degree. C. Conventionally the rail lies on one of its sides with the head and flange on the cooling panels, as shown in FIG. 1. Because of the asymmetrical profile, different cooling behavior occurs between the head and the flange of the rail. The flange cools faster than the head with the result that the cooled rail is warped. This warping can be countered to a certain degree by cambering of the still hot rail.
In any case, the cooled rail must be leveled or straightened. This is accomplished on especially equipped leveling machines. Residual stresses are set up in the rails by the cooling process and particularly by the leveling process, which can lead to a scrapping of the rail in case of unfavorable development.
Thus it is desirable to keep the residual stresses arising in the course of leveling at a reduced level, by feeding as "straight" rails as possible to the leveling machine, for instance, by cambering the rails.
Accordingly, it is an object of the present invention to provide a cooling process for hot rolled profiled rolling products, especially for rails, by which the rail can be cooled so that it is free of warping to the extent possible, and which makes it possible to minimize the residual stresses generated especially in the subsequent leveling process in the leveling machine. Another object of the present invention is to provide an apparatus for effecting the inventive process.